I was at Ridge Motorsports Park this weekend, about an hour drive away from Seattle/Tacoma area. It's a relatively new track with lots of run off. Great!

I used to run at a much smaller track near Vancouver, B.C. I never ran into any engine issue there, but again, it's a much smaller track, and it's very heavy on brakes hence sessions are usually kept short around 15 to 20 minutes.

At the Ridge, the sessions were 30 minutes each. I was able to get through Session 1 and 2 fine. By the end of the 3rd Session, I got reduced engine mode and I just can't get above ~80km/hr (~50 miles?). I didn't pay attention to the oil temp gauge at the time, because I was just trying to get my car off the track ASAP without causing any accidents or massive train build-ups. Once I got back to the paddock, I looked at the oil temp gauge and it's at the usual 120C (straight down the middle) area.

Some 2 hours later, after lunch and all, Session 4 comes along. I started the engine and all is well. After only 2 laps, I got reduced engine mode right away. Going off track, I restarted ignition, and the engine is fine aside from the fact that the engine light is still on the dash. iDrive did state that All system is green however. I was able to rev freely again. I tried to go for another lap, but reduced engine mode kicked in 2nd corner in....

I thought it's cuz I'm low on gas (1/4 tank left). I went out to get gas and came back. I then talked to a few 335 owners and they suggested me to disconnect the battery to remove the engine light first. Before that, one of them had a OBDII scanner (links to iPhone through BT). However for some reason it refused to work with my car. We disconnected the battery anyways, and after that the car came back with the engine light gone. I was able to finish off Session 5, 6 and 7 without trouble afterwards.

That said, preferably, I would much like it if I can avoid all this trouble next time around. Anybody have any clue what this might have been? Just a simple Engine Oil temp being too high? Or something else? Engine oil temp can be solved with a bigger oil cooler? Please advise. Thanks!

After I got some limp modes in July, I took my car to the dealer to find out why. The dealer said the only code they found was for some vanos thing in 2011. But I've never seen the engine light stay on after a restart.

Howard, I got the same reduced engine light after experiencing some misfire. I was able to get the code which indicated it was a misfire in cylinder #5. now after changing the plugs the car is running noticeably strong. know anyone that can give you a readout?

__________________

"I would quote everything pixelblue said, but you've already read it. Take it from someone who's put the 1 through its paces"

Can I still do a code read-out after I have disconnected and reconnected the battery? I thought that clears everything?

I am not sure whether that's true or not but without the codes it's difficult to say what could have been the problem. how many miles on your engine? do you have a tune? anyway it'll be just guess work without the codes

__________________

"I would quote everything pixelblue said, but you've already read it. Take it from someone who's put the 1 through its paces"

I had it happen on the track 3 times before I got my oil cooler and FMIC. Every time I had it happen I pulled into the pits turned car off and locked doors, unlocked doors started car boom no more limp mode. I'm not sure the new parts fixed what was happening, but I have yet to see it come back. Outdoor temps were in the low 100's every time so my issue might be more cooling related. Try my work around before going to the trouble of unhooking the battery next time and it should still have the code available once you can download it.

I had this happen to me at the track. Sounds similar, but my car never came back to normal so it could be a totally different issue. You really need a code reader if possible to help figure out the problem. I used my Cobb accessport. My code was a boost leak. A waste gate was stuck open and the turbos seized. My turbos and other stuff were all replaced under the factory warranty. Could your waste gate have been stuck open for a while then somehow started working again? I don't know.